Since resources can be removed, locking should ensure that the resource is not removed while accessing it. However, find_next_iomem_res() does not hold the lock while copying the data of the resource.
Keep holding the lock while the data is copied. While at it, change the return value to a more informative value. It is disregarded by the callers.
Fixes: ff3cc952d3f00 ("resource: Add remove_resource interface") Cc: stable@vger.kernel.org Cc: Borislav Petkov bp@suse.de Cc: Toshi Kani toshi.kani@hpe.com Cc: Peter Zijlstra peterz@infradead.org Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Dan Williams dan.j.williams@intel.com Cc: Bjorn Helgaas bhelgaas@google.com Cc: Ingo Molnar mingo@kernel.org Signed-off-by: Nadav Amit namit@vmware.com --- kernel/resource.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/kernel/resource.c b/kernel/resource.c index 158f04ec1d4f..c0f7ba0ece52 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -365,16 +365,16 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end, break; }
+ if (p) { + /* copy data */ + res->start = max(start, p->start); + res->end = min(end, p->end); + res->flags = p->flags; + res->desc = p->desc; + } + read_unlock(&resource_lock); - if (!p) - return -1; - - /* copy data */ - res->start = max(start, p->start); - res->end = min(end, p->end); - res->flags = p->flags; - res->desc = p->desc; - return 0; + return p ? 0 : -ENODEV; }
static int __walk_iomem_res_desc(resource_size_t start, resource_size_t end,